The present invention relates to methods for producing batches of containers or products wherein each batch consists of containers or products carrying a variety of differing printed images. In particular, the present invention relates to the printing of a wide variety of colour images onto the packaging of goods, such as consumer goods, or alternatively direct onto the goods themselves and producing batches of such goods such that the goods are mixed in mixed batches.
Childrenxe2x80x94and many adultsxe2x80x94enjoy collecting. A way in which to make this easy is to incorporate xe2x80x9ccollectablesxe2x80x9d as images on products or their packaging. Examples are cigarette cards and the picture cards in some tea packs. It would be advantageous to print such images on the external packaging of the product or even on the products themselves, but this has not been widely done because it is difficult to print short runs and then mix them up so that the purchaser has a choice at the point of sale.
Prior art systems exist for mixing containers or products into batches such that each batch consists of containers or products carrying a variety of differing printed images. Such prior art systems are large and complex and the mixing operation necessarily occurs after the containers or products are ready for sale.
One way of avoiding the need to mix whole containers or products is to mix pre-printed images on, for instance, cards, which are inserted into a product package such as a tea or cigarrette pack. Such mixing is relatively easy and quick to do (as compared to mixing whole containers or products). Such cards can, for instance, be mixed manually as they are loaded into a stack on the insertion machinery. See, for example, EP-A-0537149.
Another example of this manner of getting around the problems of the prior art is the use of labels which may be applied at the end of a production and packaging process. Again, it is relatively simple to mix a selection of labels and then apply them or even to print the labels just prior to the time of application. Examples of such systems are given in EP-A-0732267, EP-A-0677013.
Prior art systems also exist for printing low-quality, information-bearing labels (such as bar codes) onto products or their containers on the packaging line. See, for example, EP-A-0618141, EP-A-0088630.
Also known are relatively slow printing systems which produce printed images on demandxe2x80x94such as office computer printers or even a method of producing playing cards in a random sequence at a casino playing table (see U.S. Pat. No. 5,199,710). Such systems are not used to produce packaging for consumer goods since their speed of operation is too slow for industrial requirements.
Known techniques of high-quality, colour printing on products or product packaging require a lengthy set-up process to change an image which is being printed. The cheaper methods of printing (e.g. flexographic, gravure and offset litho) also require a substrate to be in sheet or web form so that it can be pressed onto rollers which carry the ink.
These restrictions of known techniques mean that it is difficult or expensive to print short runs, i.e. small quantities, of any given image, because the set-up time can exceed the printing time. The restrictions also mean that it is even more expensive to print onto the products themselves, unless those products happen to be in sheet or web form (e.g. when the products themselves consist of letters or the like).
Thus in prior art packaging systems, printed material (for instance packaging film) is printed with many copies of a single image before switching to another image. The same system also applies when images are printed directly onto a product. Thus, when products are manufactured and packaged using prior art systems, it is not practical to change the packaging material frequently.
With prior art systems, it is therefore not economically viable to mix a large number of images on, for instance, a point-of-sale box containing sweets. To do this, the manufacturer would have to carry large stocks of the product each with one type of image, and then mix them into each point-of-sale box. Such an operation would be expensive and would occupy a large space if more than a few different images were to be used.
Thus, using prior art packaging systems, products cannot be economically produced having a variety of images within a single batch.
The object of the present invention is to provide an industrial packaging system which allows a batch of products to be produced in an economically viable way such that each batch contains products which have different images printed on them.
A further object of the present invention is to provide a method of producing a packaged or unpackaged product in such a way that each product coming off of a production line may have a different image printed onto it (or its packaging).
The present invention provides a production, mixing and packaging method which produces a plurality of mixed groups of consumer products, wherein each of said mixed groups of consumer products comprises at least two consumer products which differ from each other in that at least a part or component of one of the at least two consumer products has an image printed onto it which is different from an image printed onto at least a part or component of another of the at least two consumer products, which said production, mixing and packaging method comprises the steps of (a) providing at least one digitally-controlled printhead at a point in a production line such that said printhead is able to print onto at least a part or component of a consumer product as it passes the or each printhead; (b) providing an image storing means which contains data relating to a plurality of different images; (c) providing an image sequencing means which sets a sequence in which said stored images are to be printed thereby determining the mix of consumer products in each mixed group of consumer products; (d) digitally controlling the printhead to print said images onto at least parts or components of a consumer products as it passes the or each printhead based on the data in the image storing means as sequenced by the image sequencing means; (e) if required, assembling a consumer product from their constituent parts or componentsxe2x80x94including the printed part(s) and/or component(s); (f) packaging a plurality of (assembled) consumer products into a single unit in order to produce one of the plurality of mixed groups of consumer products; and (g) repeating steps (d), (e) and (f), whereby, the plurality of mixed groups of consumer products are produced, mixed and packaged without there being a step of mechanically mixing products or parts or components thereof.
The present invention elegantly overcomes the problems of prior art production systems.